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<a name="Format-Commands"></a>
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<hr>
<a name="Commands-Dealing-with-Object-File-Formats"></a>
<h4 class="subsection">3.4.3 Commands Dealing with Object File Formats</h4>
<p>A couple of linker script commands deal with object file formats.
</p>
<dl compact="compact">
<dt><code>OUTPUT_FORMAT(<var>bfdname</var>)</code></dt>
<dt><code>OUTPUT_FORMAT(<var>default</var>, <var>big</var>, <var>little</var>)</code></dt>
<dd><a name="index-OUTPUT_005fFORMAT_0028bfdname_0029"></a>
<a name="index-output-file-format-in-linker-script"></a>
<p>The <code>OUTPUT_FORMAT</code> command names the BFD format to use for the
output file (see <a href="BFD.html#BFD">BFD</a>).  Using <code>OUTPUT_FORMAT(<var>bfdname</var>)</code> is
exactly like using &lsquo;<samp>--oformat <var>bfdname</var></samp>&rsquo; on the command line
(see <a href="Options.html#Options">Command Line Options</a>).  If both are used, the command
line option takes precedence.
</p>
<p>You can use <code>OUTPUT_FORMAT</code> with three arguments to use different
formats based on the &lsquo;<samp>-EB</samp>&rsquo; and &lsquo;<samp>-EL</samp>&rsquo; command line options.
This permits the linker script to set the output format based on the
desired endianness.
</p>
<p>If neither &lsquo;<samp>-EB</samp>&rsquo; nor &lsquo;<samp>-EL</samp>&rsquo; are used, then the output format
will be the first argument, <var>default</var>.  If &lsquo;<samp>-EB</samp>&rsquo; is used, the
output format will be the second argument, <var>big</var>.  If &lsquo;<samp>-EL</samp>&rsquo; is
used, the output format will be the third argument, <var>little</var>.
</p>
<p>For example, the default linker script for the MIPS ELF target uses this
command:
</p><div class="smallexample">
<pre class="smallexample">OUTPUT_FORMAT(elf32-bigmips, elf32-bigmips, elf32-littlemips)
</pre></div>
<p>This says that the default format for the output file is
&lsquo;<samp>elf32-bigmips</samp>&rsquo;, but if the user uses the &lsquo;<samp>-EL</samp>&rsquo; command line
option, the output file will be created in the &lsquo;<samp>elf32-littlemips</samp>&rsquo;
format.
</p>
</dd>
<dt><code>TARGET(<var>bfdname</var>)</code></dt>
<dd><a name="index-TARGET_0028bfdname_0029"></a>
<a name="index-input-file-format-in-linker-script"></a>
<p>The <code>TARGET</code> command names the BFD format to use when reading input
files.  It affects subsequent <code>INPUT</code> and <code>GROUP</code> commands.
This command is like using &lsquo;<samp>-b <var>bfdname</var></samp>&rsquo; on the command line
(see <a href="Options.html#Options">Command Line Options</a>).  If the <code>TARGET</code> command
is used but <code>OUTPUT_FORMAT</code> is not, then the last <code>TARGET</code>
command is also used to set the format for the output file.  See <a href="BFD.html#BFD">BFD</a>.
</p></dd>
</dl>

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